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I'm working through how the HE280 accelerometer interfaces to RAMBo. There is a 2 pin connector to the upper right of fuse 2 (when the board is held with fuse 2 on the right) that the blue wire from the HE280 whip plugs in to. I can't find this documented or labeled anywhere (http://reprap.org/wiki/Rambo_v1.3) The Repetier pins.h file has a PS_ON but I thought that was for the power supply. JJ mentioned in a text to me yesterday that it is probe switch on. Anyone have any more info?

The PS_ON connector is on the schematic over in the Power In section, not very obvious, but it is there.
Two-pin connector with VCC and PG5 pin from the CPU. The same PG5 that's on the PWM connector, as it happens.
The rest would be software changes.

I took a quick look at the firmware. In 091, it's clearly implemented as a power supply control jack, controlled by the M80 and M81 gcodes. Not terribly useful, except maybe in the early versions of the Rambo when you could still power the logic from USB without turning on the power supply.

In SeeMe's branch of 092, the jack has been repurposed for an accelerometer input. The original PS_ON function remains in the firmware, but they moved it to another pin or disabled it, depending on the configuration selected. The hardware pin definitions for Z_PROBE_PIN are hacked into configuration.h, rather than being declared in pins.h like they probably should have been. The pins.h section has become a bit of a mess as well, but oh well. It's custom, hacked, and clearly never going back to the main branch in its current form.

And based on your text, I guess they repurposed the meaning of the PS_ON label as well. Doesn't change the schematic, of course.

Thanks for the sanity check. JJ confused me with the renaming of it, he probably meant it as a joke!

It makes sense now then. The accelerometer interrupt 1 is connected to that (blue single wire) to let the firmware know a probe took place.

So is this a digital signal, like edge triggering?

[email protected] wrote:So is this a digital signal, like edge triggering?

Yes. Not sure whether it's rising or falling edge. Same concept in either case.

Hi

I am using the PS on to control the heat lamp inside the printer with ssr.
how can I install the board? where can I connect the 5v cable to?

Eric wrote:I took a quick look at the firmware. In 091, it's clearly implemented as a power supply control jack, controlled by the M80 and M81 gcodes. Not terribly useful, except maybe in the early versions of the Rambo when you could still power the logic from USB without turning on the power supply.

In SeeMe's branch of 092, the jack has been repurposed for an accelerometer input. The original PS_ON function remains in the firmware, but they moved it to another pin or disabled it, depending on the configuration selected. The hardware pin definitions for Z_PROBE_PIN are hacked into configuration.h, rather than being declared in pins.h like they probably should have been. The pins.h section has become a bit of a mess as well, but oh well. It's custom, hacked, and clearly never going back to the main branch in its current form.

And based on your text, I guess they repurposed the meaning of the PS_ON label as well. Doesn't change the schematic, of course.

Hah! So that's what they did. I had a similar accelerometer on my desk so I tried hacking it's slightly different i2c commands in place of the ones they added, but couldn't figure out what they looked at a pin that was always set to "on". Now I see they repurposed that.